Hi,
I am simulating the methane/air combustion in micro-channel using elementary reactions.

I used the seperate solver, and firstly without 'stiff chemistry solver', however the residual curve oscillate in a very large range and can't converge. Then I choose the 'stiff chemistry solver', it showed a good effect, but after about several thousands steps, there would be some errors:'ISAT reaction rate: Temperature = '.

Any sugestions? I just use the 'stiff chemistry solver' as its default values, do anyone know its appliction method or about the methane gas-phase reaction?